Conservation Tips

THERMAL UTILITIES

Boilers

Preheat combustion air with waste heat
(22 oc reduction in flue gas temperature increases boiler efficiency by 1%).
Use variable speed drives on large boiler combustion air fans with variable flows.
Burn wastes if permitted.
Insulate exposed heated oil tanks.
Clean burners, nozzles, strainers, etc.
Inspect oil heaters for proper oil temperature.
Close burner air and/or stack dampers when the burner is off to minimize heat loss up the stack.
Improve oxygen trim control (e.g. -- limit excess air to less than 10% on clean fuels). (5% reduction in excess air increases boiler efficiency by 1% or: 1% reduction of residual oxygen in stack gas increases boiler efficiency by 1%.)
Automate/optimize boiler blowdown. Recover boiler blowdown heat.
Use boiler blowdown to help warm the back-up boiler.
Optimize deaerator venting.
Inspect door gaskets.
Inspect for scale and sediment on the water side
(A 1 mm thick scale (deposit) on the water side could increase fuel consumption by 5 to 8%).
Inspect for soot, flyash, and slag on the fire side (A 3 mm thick soot deposition on the heat transfer surface can cause an increase in fuel consumption to the tune of 2.5%.)
Optimize boiler water treatment.
Add an economizer to preheat boiler feedwater using exhaust heat.
Recycle steam condensate.
Study part-load characteristics and cycling costs to determine the most-efficient mode for operating multiple boilers.
Consider multiple or modular boiler units instead of one or two large boilers.
Establish a boiler efficiency-maintenance program. Start with an energy audit and follow-up, then make a boiler efficiency-maintenance program a part of your continuous energy management program.

Steam System

Fix steam leaks and condensate leaks (A 3 mm diameter hole on a pipe line carrying 7 kg/cm2 steam would waste 33 kilo litres of fuel oil per year).
Accumulate work orders for repair of steam leaks that can't be fixed during the heating season due to system shutdown requirements. Tag each such leak with a durable tag with a good description.
Use back pressure steam turbines to produce lower steam pressures.
Use more-efficient steam desuperheating methods.
Ensure process temperatures are correctly controlled.
Maintain lowest acceptable process steam pressures.
Reduce hot water wastage to drain.
Remove or blank off all redundant steam piping.
Ensure condensate is returned or re-used in the process(6 0C raise in feed water temperature by economiser/condensate recovery
corresponds to a 1% saving in fuel consumption, in boiler).
Preheat boiler feed-water.
Recover boiler blowdown.
Check operation of steam traps.
Remove air from indirect steam using equipment (0.25 mm thick air film offers the same resistance to heat transfer as a 330 mm thick copper wall.)
Inspect steam traps regularly and repair malfunctioning traps promptly.
Consider recovery of vent steam (e.g. -- on large flash tanks).
Use waste steam for water heating.
Use an absorption chiller to condense exhaust steam before returning the condensate to the boiler.
Use electric pumps instead of steam ejectors when cost benefits permit
Establish a steam efficiency-maintenance program. Start with an energy audit and follow-up, then make a steam efficiency-maintenance program a part of your continuous energy management program.

Furnaces

Check against infiltration of air: Use doors or air curtains.
Monitor O2 /CO2/CO and control excess air to the optimum level.
Improve burner design, combustion control and instrumentation.
Ensure that the furnace combustion chamber is under slight positive pressure.
Use ceramic fibres in the case of batch operations.
Match the load to the furnace capacity.
Retrofit with heat recovery device.
Investigate cycle times and reduce.
Provide temperature controllers.
Ensure that flame does not touch the stock.

Insulation

Repair damaged insulation (A bare steam pipe of 150 mm diameter and 100 m length, carrying saturated steam at 8 kg/cm2 would waste 25,000 litres furnace oil in a year.)
Insulate any hot or cold metal or insulation.
Replace wet insulation.
Use an infrared gun to check for cold wall areas during cold weather or hot wall areas during hot weather.
Ensure that all insulated surfaces are cladded with aluminum
Insulate all flanges, valves and couplings
Insulate open tanks (70% heat losses can be reduced by floating a layer of 45 mm diameter polypropylene (plastic) balls on the surface of 90 0 C hot liquid/condensate).

Waste heat recovery

Recover heat from flue gas, engine cooling water, engine exhaust, low pressure waste steam, drying oven exhaust, boiler blowdown, etc.
Recover heat from incinerator off-gas.
Use waste heat for fuel oil heating, boiler feedwater heating, outside air heating, etc.
Use chiller waste heat to preheat hot water.
Use heat pumps.
Use absorption refrigeration.
Use thermal wheels, run-around systems, heat pipe systems, and air-to-air exchangers.

ELECTRICAL UTILITIES

Electricity Distribution System

Optimise the tariff structure with utility supplier
Schedule your operations to maintain a high load factor
Shift loads to off-peak times if possible.
Minimise maximum demand by tripping loads through a demand controller
Stagger start-up times for equipment with large starting currents to minimize load peaking.
Use standby electric generation equipment for on-peak high load periods.
Correct power factor to at least 0.90 under rated load conditions.
Relocate transformers close to main loads.
Set transformer taps to optimum settings.
Disconnect primary power to transformers that do not serve any active loads
Consider on-site electric generation or cogeneration.
Export power to grid if you have any surplus in your captive generation
Check utility electric meter with your own meter.
Shut off unnecessary computers, printers, and copiers at night.

Motors

Properly size to the load for optimum efficiency.(High efficiency motors offer of 4 - 5% higher efficiency than standard motors)
Use energy-efficient motors where economical.
Use synchronous motors to improve power factor.
Check alignment.
Provide proper ventilation(For every 10 o C increase in motor operating temperature over recommended peak, the motor life is estimated to be halved)
Check for under-voltage and over-voltage conditions.
Balance the three-phase power supply.(An imbalanced voltage can reduce 3 - 5% in motor input power)
Demand efficiency restoration after motor rewinding.(If rewinding is not done properly, the efficiency can be reduced by 5 - 8%)

Drives

Use variable-speed drives for large variable loads.
Use high-efficiency gear sets.
Use precision alignment.
Check belt tension regularly.
Eliminate variable-pitch pulleys.
Use flat belts as alternatives to v-belts.
Use synthetic lubricants for large gearboxes.
Eliminate eddy current couplings.
Shut them off when not needed.

Fans

Use smooth, well-rounded air inlet cones for fan air intakes.
Avoid poor flow distribution at the fan inlet.
Minimize fan inlet and outlet obstructions.
Clean screens, filters, and fan blades regularly.
Use aerofoil-shaped fan blades.
Minimize fan speed.
Use low-slip or flat belts.
Check belt tension regularly.
Eliminate variable pitch pulleys.
Use variable speed drives for large variable fan loads.
Use energy-efficient motors for continuous or near-continuous operation
Eliminate leaks in ductwork.
Minimise bends in ductwork
Turn fans off when not needed.

Blowers

Use smooth, well-rounded air inlet ducts or cones for air intakes.
Minimize blower inlet and outlet obstructions.
Clean screens and filters regularly.
Minimize blower speed.
Use low-slip or no-slip belts.
Check belt tension regularly.
Eliminate variable pitch pulleys.
Use variable speed drives for large variable blower loads.
Use energy-efficient motors for continuous or near-continuous operation.
Eliminate ductwork leaks.
Turn blowers off when they are not needed

Pumps

Operate pumping near best efficiency point.
Modify pumping to minimize throttling.
Adapt to wide load variation with variable speed drives or sequenced control of smaller units.
Stop running both pumps -- add an auto-start for an on-line spare or add a booster pump in the problem area.
Use booster pumps for small loads requiring higher pressures.
Increase fluid temperature differentials to reduce pumping rates.
Repair seals and packing to minimize water waste.
Balance the system to minimize flows and reduce pump power requirements.
Use siphon effect to advantage: don't waste pumping head with a free-fall (gravity)
return.

Compressors

Consider variable speed drive for variable load on positive displacement compressors.
Use a synthetic lubricant if the compressor manufacturer permits it.
Be sure lubricating oil temperature is not too high (oil degradation and lowered viscosity) and not too low (condensation contamination).
Change the oil filter regularly.
Periodically inspect compressor intercoolers for proper functioning.
Use waste heat from a very large compressor to power an absorption chiller or preheat process or utility feeds.
Establish a compressor efficiency-maintenance program. Start with an energy audit and follow-up, then make a compressor efficiency-maintenance program a part of
your continuous energy management program.

Compressed air

Install a control system to coordinate multiple air compressors.
Study part-load characteristics and cycling costs to determine the most-efficient mode for operating multiple air compressors.
Avoid over sizing -- match the connected load.
Load up modulation-controlled air compressors. (They use almost as much power at partial load as at full load.)
Turn off the back-up air compressor until it is needed.
Reduce air compressor discharge pressure to the lowest acceptable setting. (Reduction of 1 kg/cm2 air pressure (8 kg/cm2 to 7 kg/cm2) would result in 9% input
power savings. This will also reduce compressed air leakage rates by 10%)
Use the highest reasonable dryer dew point settings.
Turn off refrigerated and heated air dryers when the air compressors are off.
Use a control system to minimize heatless desiccant dryer purging.
Minimize purges, leaks, excessive pressure drops, and condensation accumulation.(Compressed air leak from 1 mm hole size at 7 kg/cm2 pressure would mean power
loss equivalent to 0.5 kW)
Use drain controls instead of continuous air bleeds through the drains.
Consider engine-driven or steam-driven air compression to reduce electrical demand charges.
Replace standard v-belts with high-efficiency flat belts as the old v-belts wear out.
Use a small air compressor when major production load is off.
Take air compressor intake air from the coolest (but not air conditioned) location.(Every 50C reduction in intake air temperature would result in 1% reduction in compressor power consumption)
Use an air-cooled aftercooler to heat building makeup air in winter.
Be sure that heat exchangers are not fouled (e.g. -- with oil).
Be sure that air/oil separators are not fouled.
Monitor pressure drops across suction and discharge filters and clean or replace filters promptly upon alarm.
Use a properly sized compressed air storage receiver. Minimize disposal costs by using lubricant that is fully demulsible and an effective oil-water separator.
Consider alternatives to compressed air such as blowers for cooling, hydraulic rather than air cylinders, electric rather than air actuators, and electronic rather than pneumatic controls.
Use nozzles or venturi-type devices rather than blowing with open compressed air lines.
Check for leaking drain valves on compressed air filter/regulator sets. Certain rubbertype valves may leak continuously after they age and crack.
In dusty environments, control packaging lines with high-intensity photocell units instead of standard units with continuous air purging of lenses and reflectors.
Establish a compressed air efficiency-maintenance program. Start with an energy audit and follow-up, then make a compressed air efficiency-maintenance program a
part of your continuous energy management program.

Chillers

Increase the chilled water temperature set point if possible.
Use the lowest temperature condenser water available that the chiller can handle.(Reducing condensing temperature by 5.5 0C, results in a 20 - 25% decrease in compressor power consumption)
Increase the evaporator temperature(5.50C increase in evaporator temperature reduces compressor power consumption by 20 - 25%)
Clean heat exchangers when fouled.(1 mm scale build-up on condenser tubes can increase energy consumption by 40%)
Optimize condenser water flow rate and refrigerated water flow rate.
Replace old chillers or compressors with new higher-efficiency models.
Use water-cooled rather than air-cooled chiller condensers.
Use energy-efficient motors for continuous or near-continuous operation.
Specify appropriate fouling factors for condensers.
Do not overcharge oil.
Install a control system to coordinate multiple chillers.
Study part-load characteristics and cycling costs to determine the most-efficient mode for operating multiple chillers.
Run the chillers with the lowest energy consumption. It saves energy cost, fuels a base load.
Avoid oversizing -- match the connected load.
Isolate off-line chillers and cooling towers.
Establish a chiller efficiency-maintenance program. Start with an energy audit and follow-up, then make a chiller efficiency-maintenance program a part of your
continuous energy management program.

HVAC (Heating / Ventilation / Air Conditioning)

Tune up the HVAC control system.
Consider installing a building automation system (BAS) or energy management system (EMS) or restoring an out-of-service one.
Balance the system to minimize flows and reduce blower/fan/pump power requirements.
Eliminate or reduce reheat whenever possible.
Use appropriate HVAC thermostat setback.
Use morning pre-cooling in summer and pre-heating in winter (i.e. -- before electrical peak hours).
Use building thermal lag to minimize HVAC equipment operating time.
In winter during unoccupied periods, allow temperatures to fall as low as possible without freezing water lines or damaging stored materials.
In summer during unoccupied periods, allow temperatures to rise as high as possible without damaging stored materials.
Improve control and utilization of outside air.
Use air-to-air heat exchangers to reduce energy requirements for heating and cooling of outside air.
Reduce HVAC system operating hours (e.g. -- night, weekend).
Optimize ventilation.
Ventilate only when necessary. To allow some areas to be shut down when unoccupied, install dedicated HVAC systems on continuous loads (e.g. -- computer
rooms).
Provide dedicated outside air supply to kitchens, cleaning rooms, combustion equipment, etc. to avoid excessive exhausting of conditioned air.
Use evaporative cooling in dry climates.
Reduce humidification or dehumidification during unoccupied periods.
Use atomization rather than steam for humidification where possible.
Clean HVAC unit coils periodically and comb mashed fins.
Upgrade filter banks to reduce pressure drop and thus lower fan power requirements.
Check HVAC filters on a schedule (at least monthly) and clean/change if appropriate.
Check pneumatic controls air compressors for proper operation, cycling, and maintenance.
Isolate air conditioned loading dock areas and cool storage areas using high-speed doors or clear PVC strip curtains.
Install ceiling fans to minimize thermal stratification in high-bay areas.
Relocate air diffusers to optimum heights in areas with high ceilings.
Consider reducing ceiling heights.
Eliminate obstructions in front of radiators, baseboard heaters, etc.
Check reflectors on infrared heaters for cleanliness and proper beam direction.
Use professionally-designed industrial ventilation hoods for dust and vapor control.
Use local infrared heat for personnel rather than heating the entire area.
Use spot cooling and heating (e.g. -- use ceiling fans for personnel rather than cooling the entire area).
Purchase only high-efficiency models for HVAC window units.
Put HVAC window units on timer control.
Don't oversize cooling units. (Oversized units will "short cycle" which results in poor humidity control.)
Install multi-fueling capability and run with the cheapest fuel available at the time.
Consider dedicated make-up air for exhaust hoods. (Why exhaust the air conditioning or heat if you don't need to?)
Minimize HVAC fan speeds.
Consider desiccant drying of outside air to reduce cooling requirements in humid climates.
Consider ground source heat pumps.
Seal leaky HVAC ductwork.
Seal all leaks around coils.
Repair loose or damaged flexible connections (including those under air handling units).
Eliminate simultaneous heating and cooling during seasonal transition periods.
Zone HVAC air and water systems to minimize energy use.
Inspect, clean, lubricate, and adjust damper blades and linkages.
Establish an HVAC efficiency-maintenance program. Start with an energy audit and follow-up, then make an HVAC efficiency-maintenance program a part of your
continuous energy management program.

Refrigeration

Use water-cooled condensers rather than air-cooled condensers.
Challenge the need for refrigeration, particularly for old batch processes.
Avoid oversizing -- match the connected load.
Consider gas-powered refrigeration equipment to minimize electrical demand charges.
Use "free cooling" to allow chiller shutdown in cold weather.
Use refrigerated water loads in series if possible.
Convert firewater or other tanks to thermal storage.
Don't assume that the old way is still the best -- particularly for energy-intensive low temperature systems.
Correct inappropriate brine or glycol concentration that adversely affects heat transfer and/or pumping energy. If it sweats, insulate it, but if it is corroding, replace it first.
Make adjustments to minimize hot gas bypass operation.
Inspect moisture/liquid indicators.
Consider change of refrigerant type if it will improve efficiency.
Check for correct refrigerant charge level.
Inspect the purge for air and water leaks.
Establish a refrigeration efficiency-maintenance program. Start with an energy audit and follow-up, then make a refrigeration efficiency-maintenance program a part of your continuous energy management program.

Cooling towers

Control cooling tower fans based on leaving water temperatures.
Control to the optimum water temperature as determined from cooling tower and chiller performance data.
Use two-speed or variable-speed drives for cooling tower fan control if the fans are few. Stage the cooling tower fans with on-off control if there are many.
Turn off unnecessary cooling tower fans when loads are reduced.
Cover hot water basins (to minimize algae growth that contributes to fouling).
Balance flow to cooling tower hot water basins.
Periodically clean plugged cooling tower water distribution nozzles.
Install new nozzles to obtain a more-uniform water pattern.
Replace splash bars with self-extinguishing PVC cellular-film fill.
On old counterflow cooling towers, replace old spray-type nozzles with new squarespray ABS practically-non-clogging nozzles.
Replace slat-type drift eliminators with high-efficiency, low-pressure-drop, selfextinguishing, PVC cellular units.
If possible, follow manufacturer's recommended clearances around cooling towers and relocate or modify structures, signs, fences, dumpsters, etc. that interfere with air intake or exhaust.
Optimize cooling tower fan blade angle on a seasonal and/or load basis.
Correct excessive and/or uneven fan blade tip clearance and poor fan balance.
Use a velocity pressure recovery fan ring.
Divert clean air-conditioned building exhaust to the cooling tower during hot weather.
Re-line leaking cooling tower cold water basins.
Check water overflow pipes for proper operating level.
Optimize chemical use.
Consider side stream water treatment.
Restrict flows through large loads to design values.
Shut off loads that are not in service.
Take blowdown water from the return water header.
Optimize blowdown flow rate.
Automate blowdown to minimize it.
Send blowdown to other uses (Remember, the blowdown does not have to be removed at the cooling tower. It can be removed anywhere in the piping system.)
Implement a cooling tower winterization plan to minimize ice build-up.
Install interlocks to prevent fan operation when there is no water flow.
Establish a cooling tower efficiency-maintenance program. Start with an energy audit and follow-up, then make a cooling tower efficiency-maintenance program a part of your continuous energy management program.

Lighting

Reduce excessive illumination levels to standard levels using switching, delamping, etc. (Know the electrical effects before doing delamping.)
Aggressively control lighting with clock timers, delay timers, photocells, and/or occupancy sensors.
Install efficient alternatives to incandescent lighting, mercury vapor lighting, etc. Efficacy (lumens/watt) of various technologies range from best to worst
approximately as follows: low pressure sodium, high pressure sodium, metal halide, fluorescent, mercury vapor, incandescent.
Select ballasts and lamps carefully with high power factor and long-term efficiency in mind.
Upgrade obsolete fluorescent systems to Compact fluorescents and electronic ballasts
Consider daylighting, skylights, etc.
Consider painting the walls a lighter color and using less lighting fixtures or lower wattages.
Use task lighting and reduce background illumination.
Re-evaluate exterior lighting strategy, type, and control. Control it aggressively.
Change exit signs from incandescent to LED.

DG sets

Optimise loading
Use waste heat to generate steam/hot water /power an absorption chiller or preheat process or utility feeds.
Use jacket and head cooling water for process needs
Clean air filters regularly
Insulate exhaust pipes to reduce DG set room temperatures
Use cheaper heavy fuel oil for capacities more than 1MW

Buildings

Seal exterior cracks/openings/gaps with caulk, gasketing, weatherstripping, etc.
Consider new thermal doors, thermal windows, roofing insulation, etc.
Install windbreaks near exterior doors.
Replace single-pane glass with insulating glass.
Consider covering some window and skylight areas with insulated wall panels inside the building.
If visibility is not required but light is required, consider replacing exterior windows with insulated glass block.
Consider tinted glass, reflective glass, coatings, awnings, overhangs, draperies, blinds, and shades for sunlit exterior windows.
Use landscaping to advantage.
Add vestibules or revolving doors to primary exterior personnel doors.
Consider automatic doors, air curtains, strip doors, etc. at high-traffic passages between conditioned and non-conditioned spaces. Use self-closing doors if possible.
Use intermediate doors in stairways and vertical passages to minimize building stack effect.
Use dock seals at shipping and receiving doors.
Bring cleaning personnel in during the working day or as soon after as possible to minimize lighting and HVAC costs.

Water & Wastewater

Recycle water, particularly for uses with less-critical quality requirements.
Recycle water, especially if sewer costs are based on water consumption.
Balance closed systems to minimize flows and reduce pump power requirements.
Eliminate once-through cooling with water.
Use the least expensive type of water that will satisfy the requirement.
Fix water leaks.
Test for underground water leaks. (It's easy to do over a holiday shutdown.)
Check water overflow pipes for proper operating level.
Automate blowdown to minimize it.
Provide proper tools for wash down -- especially self-closing nozzles.
Install efficient irrigation.
Reduce flows at water sampling stations.
Eliminate continuous overflow at water tanks.
Promptly repair leaking toilets and faucets.
Use water restrictors on faucets, showers, etc.
Use self-closing type faucets in restrooms.
Use the lowest possible hot water temperature.
Do not use a central heating system hot water boiler to provide service hot water during the cooling season -- install a smaller, more-efficient system for the cooling season service hot water.
Consider the installation of a thermal solar system for warm water.
If water must be heated electrically, consider accumulation in a large insulated storage tank to minimize heating at on-peak electric rates.
Use multiple, distributed, small water heaters to minimize thermal losses in large piping systems.
Use freeze protection valves rather than manual bleeding of lines.
Consider leased and mobile water treatment systems, especially for deionized water.
Seal sumps to prevent seepage inward from necessitating extra sump pump operation.
Install pretreatment to reduce TOC and BOD surcharges.
Verify the water meter readings. (You'd be amazed how long a meter reading can be estimated after the meter breaks or the meter pit fills with water!)
Verify the sewer flows if the sewer bills are based on them

Miscellaneous

Meter any unmetered utilities. Know what is normal efficient use. Track down causes of deviations.
Shut down spare, idling, or unneeded equipment.
Make sure that all of the utilities to redundant areas are turned off -- including utilities like compressed air and cooling water.
Install automatic control to efficiently coordinate multiple air compressors, chillers, cooling tower cells, boilers, etc.
Renegotiate utilities contracts to reflect current loads and variations.
Consider buying utilities from neighbors, particularly to handle peaks.
Leased space often has low-bid inefficient equipment. Consider upgrades if your lease will continue for several more years.
Adjust fluid temperatures within acceptable limits to minimize undesirable heat transfer in long pipelines.
Minimize use of flow bypasses and minimize bypass flow rates.
Provide restriction orifices in purges (nitrogen, steam, etc.).
Eliminate unnecessary flow measurement orifices.
Consider alternatives to high pressure drops across valves.
Turn off winter heat tracing that is on in summer.

Conservation Tips

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